Cruise ship outbreaks can be worse than reported

WASHINGTON — The number of passengers sickened in norovirus outbreaks on cruise ships can often be higher than reported, according to the USA Today.

Researchers from the U.S. Centers for Disease Control and Prevention (CDC) believe that 40 percent of passengers who fell ill during a closely studied outbreak of norovirus on a ship in 2009 failed to inform the vessel''s infirmary, which left their illness out of the official tallies, the article stated.

An investigation of the outbreak while it was ongoing by CDC staffers who boarded the ship found that 15.4 percent of passengers had become sick, but only 60 percent of the ill passengers had made their illness known to ship officials, the article noted.

According to the article, a number of passengers said they would not report their illness because they were worried about having to pay for treatment.